Our OBS Plugin, available on the "latest" branch, allows you to "Export" any scene or source to be used as your LIV camera, without any CPU overhead!
Close LIV, then go to Steam > LIV > Properties > Betas, and select "latest - Warning!" there
You can find it in LIV's Resources\OBS Plugin folder, and you'll need to install it and add it to a scene/source before using it in LIV
Program Files (x86)\Steam\steamapps\common\LIV\Resources\OBS Plugin copy that over to Program Files\obs-studio and choose Replace files when prompted to do so.
If you installed OBS through Steam: Program Files (x86)\Steam\steamapps\common\OBS Studio
In OBS
Right click the scene or source and select Filters
Then click the + to select the filter LIV: Export As Camera
IN LIV
Create a new camera profile
Select OBS Source in the Type: drop down menu
Continue on as normal from here.